1. Aim # 28: What is the difference between an acid and a base?
H.W. # 28
Review p Study pp Ans. ques. p. 532 # p. 246 # 17,18,21-23

2. I Properties of acids Acids are molecular substances whose water solutions produce H+ ions as the only positive ions in solution. The properties of acids are due to this excess of H+ ions.
Acids conduct electricity- they are electrolytes.
will react with metals above H in Ref. Table J to produce H2 gas.
Acids cause color changes to acid-base indicators. Ref. Table M common acid-base indicators
Dilute aqueous solutions of acids have a sour taste. e.g. lemons, limes, and vinegar all contain acid.

3. Complete the following equation for the ionization of NaOH(s) in water. NaOH(s) +H2O →
II Base (Arrhenious’ definition)- a substance whose water solution yields hydroxide ions (OH-) as the only negative ion in solution.
e.g. NaOH(s) + H2O(l) → Na+(aq) + OH-(aq)
NH3(g) + H2O(l) → NH4+(aq) + OH-(aq)
Ref. Table L
common bases

4. III Properties of bases
Aqueous solutions of bases conduct electricity- they are electrolytes.
Bases cause color changes to acid-base indicators Ref. Table M
Bases react with acids to form a salt and water. (neutralization) e.g. NaOH(aq) + HCl(aq) → NaCl(aq) + H2O(l)
Aqueous solutions of bases feel slippery.

5. IV Salts- a salt is an ionic compound containing a positive ion other than H+ and a negative ion other than OH-.
e.g. HCl(aq) hydrochloric acid
KCl potassium chloride
Ca(OH)2 calcium hydroxide
CaBr calcium bromide
Remember,
Acid + Base → Salt + Water (neutralization reaction)
e.g. 2HCl(aq) + Ca(OH)2(aq) → CaCl2(aq) + H2O(l)